1. Field of the Invention
The present invention relates to a production system for producing electrolyzed water by electrolysis of brine in an electrolyzer.
2. Description of the Prior Art
Illustrated in FIG. 8 is a conventional production system of electrolyzed water of the type which includes a saturated brine tank 70 arranged to store saturated brine prepared by dissolution of water-soluble salt S such as table salt, a diluted brine tank 72 arranged to store diluted brine prepared by dilution of the saturated brine supplied from the saturated brine tank 70 through a discharge conduit 71 and an electrolyzer 90 provided therein with an anode 91 and a cathode 92 for electrolyzing the diluted brine supplied from the diluted brine tank 72 by means of hydraulic pumps 80 and 81 for production of acidic water and alkaline water. In the production system of electrolyzed water, the level of diluted brine in tank 72 drops due to continuous supply of the diluted brine into the electrolyzer 90. Thus, the production system is provided with a liquid surface sensor 73 for detecting the level of diluted brine in tank 72, a density sensor 74 for detecting concentration of the diluted brine and an electronic controller (not shown) responsive to electric signals from the sensors 73 and 74 for controlling each operation of a water supply valve 75 and a pinch valve 76 in such a manner that the level and concentration of diluted brine in tank 72 are maintained higher than a predetermined value. When the saturated brine is supplied into the diluted brine tank 72 from the saturated brine tank 70 to properly prepare the concentration of diluted brine in tank 72, the level of saturated brine in tank 70 drops. When the drop of the level of saturated brine in tank 70 is detected by a liquid surface sensor 77, the controller acts to open a water supply valve 78 in response to an electric signal from the liquid surface sensor 77 for supplying fresh water into the saturated brine tank 70 until the level of saturated brine rises up to a predetermined level.
In such a conventional production system of electrolyzed water as described above, however, the temperature of brine, the hardness of water or the DC voltage applied to the electrolyzer fluctuates due to change of the season or environments. This results in change of the efficiency of electrolysis in the electrolyzer 90. It is, therefore, difficult to constantly produce electrolyzed water with a desired chemical property.